Mechanical and tribological behavior of multilayer and monolayer TiN-based coatings

This study investigates the mechanical and tribological properties of monolayer TiN coatings and multilayer TiN/TiCN coatings deposited via direct current magnetron sputtering onto titanium substrates (VT1-0). The coatings were characterized by microstructure, nanohardness, elastic modulus, and tribological performance under lubricated friction conditions. Scanning electron microscopy (SEM) revealed that the coatings exhibit a uniform microstructure without visible defects and a typical columnar growth morphology. Nanoindentation tests demonstrated that the multilayer TiN/TiCN coatings possess enhanced hardness (up to 23.5 GPa) and elastic modulus (191 GPa) compared to the monolayer TiN, attributed to interlayer strengthening effects and redistribution of residual stresses. Tribological tests using a ball-on-disk configuration under lubricated conditions showed that the multilayer coatings exhibit a significantly lower coefficient of friction (0.10–0.13) and improved wear resistance compared to the TiN coating. This behavior is associated with TiCN layers, which reduce interfacial adhesion, promote uniform load distribution, and facilitates the formation of a protective tribofilm. The results confirm that the TiN/TiCN multilayer coatings offer superior mechanical and tribological properties, making them promising candidates for engineering components operating under friction and wear conditions.